PROJECT SUMMARY Young Black gay, bisexual and other men who have sex with men (YB-GBMSM) experience high HIV prevalence and incidence, but suboptimal rates of engagement across the HIV Continuum of Care (HIV-CoC). Treatable mental health (MH) conditions such as depressive disorders, anxiety disorders, trauma- and stressor-related disorders, and substance use are major determinants of HIV-CoC outcomes; however, MH services utilization rates are low in this population. There is a need for culturally -tailored interventions to improve MH service utilization among YB-GBMSM, in order to improve both HIV-CoC and MH outcomes. Our long-term goal is to identify novel approaches to promoting and delivering MH services for YB-GBMSM living with HIV. The objective of this R21 application is to develop an understanding of influences on MH service utilization among YB-GBMSM living with HIV. The rationale for the project is that the influences on HIV and MH care are often overlapping and/or synergistic, and that cultural considerations are critically important to understanding these factors. Our study will be based in Atlanta, Georgia ? an HIV epicenter. The theoretical foundation for the study is a preliminary conceptual model based on Andersen?s Behavioral Model of Health Service Use, which we have culturally adapted using theories and frameworks with particular relevance for YB- GBMSM (minority stress, intersectionality, and resilience). This study will pursue three specific aims: (1) to qualitatively explore conceptualizations of MH service utilization among YB-GBMSM living with HIV, including investigation of associated sociocultural, demographic and clinical influences; (2) to quantitatively examine relationships between constructs in our conceptual model, MH service utilization, and HIV-CoC outcomes; and (3) To develop program objectives and methods for a culturally-tailored intervention designed to enhance acceptability and uptake of MH services, and improve HIV-CoC outcomes, among YB-GBMSM living with HIV. For the first aim, we will conduct N=40 qualitative interviews to understand conceptualizations of MH and MH services, and to refine a conceptual model based on Andersen?s Behavioral Model. For the second aim, we will test the relationships in our model using quantitative data from N=200 cross-sectional surveys that we will conduct with YB-GBMSM living with HIV. For the third aim, we will synthesize the findings from Aims 1 and 2 to begin development of an intervention to enhance MH service utilization among YB-GBMSM living with HIV, using the Intervention Mapping approach. The proposed research is highly significant because of its potential to inform effective strategies for improving HIV-CoC outcomes among YB-GBMSM, with important implications for both individual and public health outcomes.